ISet<T>.IsProperSubsetOf Method (IEnumerable<T>)


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Determines whether the current set is a proper (strict) subset of a specified collection.

Namespace:   System.Collections.Generic
Assembly:  System (in System.dll)

bool IsProperSubsetOf(
	IEnumerable<T> other


Type: System.Collections.Generic.IEnumerable<T>

The collection to compare to the current set.

Return Value

Type: System.Boolean

true if the current set is a proper subset of other; otherwise, false.

Exception Condition

other is null.

If the current set is a proper subset of other, other must have at least one element that the current set does not have.

An empty set is a proper subset of any other collection. Therefore, this method returns true if the current set is empty, unless the other parameter is also an empty set.

This method always returns false if the current set has more or the same number of elements than other.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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